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 ###Instrução: Qual foi a pontuação vencedora do Buy.com Siouxland Open?
 ###Tabelas: CREATE TABLE grand_prix_standings (grand_prix_standings_id AUTO_INCREMENT PRIMARY KEY, Player VARCHAR, Qual. VARCHAR, Baku VARCHAR, Sochi VARCHAR, Elista VARCHAR, Nalchik VARCHAR, Jermuk VARCHAR, Astrakhan VARCHAR, Played INT) CREATE TABLE practice_times_and_leaderboard_600cc (practice_times_and_leaderboard_600cc_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Rider VARCHAR, Sat 29 May VARCHAR, Mon 31 May VARCHAR, Tues 1 June VARCHAR, Wed 2 June VARCHAR, Thurs 3 June VARCHAR, Fri 4 June VARCHAR) CREATE TABLE nationwide_tour_wins_5 (nationwide_tour_wins_5_id AUTO_INCREMENT PRIMARY KEY, Date VARCHAR, Tournament VARCHAR, Winning score VARCHAR, Margin of victory VARCHAR, Runner(s)-up VARCHAR) CREATE TABLE revenues_from_stamp_duties (revenues_from_stamp_duties_id AUTO_INCREMENT PRIMARY KEY, Year VARCHAR, Stamp duty reserve tax VARCHAR, Standard Stamp Duty VARCHAR, Standard Duties Total Revenue (in €million) INT, over Total Tax Revenue (in %) VARCHAR, over GDP (in %) VARCHAR) CREATE TABLE all-time_results_record (all-time_results_record_id AUTO_INCREMENT PRIMARY KEY, Team VARCHAR, First Played INT, Played INT, Win INT, Draw INT, Loss INT, Points For INT, Ponts Against INT, Last Meeting INT)  
SELECT Winning score FROM nationwide_tour_wins_5 WHERE Tournament = buy.com siouxland open